This is a breakdown of the System III Identifiers (Surgard).
("0", Protocols.SIA);
("1@",Protocols.HeartBeat);
("1", Protocols.Basic);
("3", Protocols.DVAC);
("4", Protocols.CallerID)
("5", Protocols.ContactID);
("6", Protocols.ModemII);
("7", Protocols.Sescoa);
("8", Protocols.AdemcoHighSpeed);
("9", Protocols.Acron);
("C", Protocols.SKFSK);
("E", Protocols.SKFSK);
("F", Protocols.SKFSK);
("G", Protocols.CESA);
("H", Protocols.Robofon);
("I", Protocols.ITI);
("J", Protocols.FBI);
("L", Protocols.Outel);
("N", Protocols.Stratel);
("P", Protocols.DMP);
("Q", Protocols.ContactID);
("a", Protocols.Paradox);
("R", Protocols.SIA);
("S", Protocols.SIA);
("T", Protocols.Telenot);
("U", Protocols.InternationalCallerID);
("V", Protocols.Vonk);
("W", Protocols.Westec);
("Y", Protocols.Surtec);
("Z", Protocols.Basic);
("e", Protocols.ADTPulse);
("s", Protocols.SIMNumber);
("u", Protocols.CallingName);